Fixed back navigation

app/src/main/java/eu/faircode/email/ActivityView.java

@@ -304,6 +304,7 @@ public class ActivityView extends ActivityBilling implements FragmentManager.OnB
             setIntent(intent);
 
             intent.putExtra("thread", action.split(":", 2)[1]);
+            getSupportFragmentManager().popBackStack("unified", 0);
             onViewThread(intent);
         }
     }
@@ -766,8 +767,6 @@ public class ActivityView extends ActivityBilling implements FragmentManager.OnB
     }
 
     private void onViewThread(Intent intent) {
-        getFragmentManager().popBackStack("thread", FragmentManager.POP_BACK_STACK_INCLUSIVE);
-
         Bundle args = new Bundle();
         args.putLong("account", intent.getLongExtra("account", -1));
         args.putString("thread", intent.getStringExtra("thread"));